Bionomía y ecología poblacional de la trucha arcoiris, Oncorhynchus mykiss neisoni (Evermann), de la Sierra San Pedro Mártir, Baja California, México

Tesis (Doctor en Ciencias con Especialidad en Ecología Acúatica y Pesca) U.A.N.L.UANLhttp://www.uanl.mx

RELACIONES PESO-LONGITUD Y LONGITUD PATRÓN-LONGITUD TOTAL PARA 12 ESPECIES DE PECES DE UN ECOSISTEMA ESTUARINO DEL GOLFO DE CALIFORNIA, MÉXICO

Length - weight (LW) and standard length - total length (LL) relationships were assessed for 12 fish species caught in the Mulege River estuary (middle Gulf of California), Mexico. Fish were sampled in November 2011 and January 2012, using cast nets and gill nets (mesh size 3 mm). Parameters of the LW and LL relationships were estimated using the log-linear and simple linear regressions. Values of b parameter ranged from 2.39 in Lile stolifera (Jordan & Gilbert, 1882) to 3.16 in Mugil curema Valenciennes, 1836. LL relationships were significantly correlated, ranging 0.851 to 0.999. This study reports for the first time, LL relationships for three species (Ctenogobius sagittula (Günther, 1861), Erotelis armiger (Jordan & Richardson, 1895), and L. nigrofasciata Castro-Aguirre, Ruiz-Campos & Balart, 2002). The information reported here will be useful to generate a baseline for regulation as well as for a sustainable fishery management in one of the two positive estuarine ecosystems known in the Gulf of California.Las relaciones Peso - longitud (LW) y longitud patrón- longitud total (LL), fueron evaluadas para 12 especie de peces capturados en el estuario del Río Mulegé (parte media del Golfo de California). Los peces fueron recolectados en noviembre de 2011 y enero de 2012, utilizando atarraya y redes de enmalle (luz de malla 3 mm). Los parámetros de las relaciones LW y LL fueron estimados mediante regresión logtransformada y lineal simple. Los valores del parámetro b variaron de 2.39 en Lile stolifera (Jordan & Gilbert, 1882) a 3.16 en Mugil curema Valenciennes, 1836. Las relaciones LL mostraron correlación significante, variando de 0.851 a 0.999. Se reporta por primera vez la relación LL para tres especies (Ctenogobius sagittula (Günther, 1861), Erotelis armiger (Jordan & Richardson, 1895) and L. nigrofasciata Castro-Aguirre, Ruiz-Campos & Balart, 2002). La información aquí reportada servirá para generar líneas base para la regulación y un manejo sustentable de las pesquerías en uno de los dos estuarios positivos en el Golfo de California

Morphometric Comparison of Blue Catfish Ictalurus furcatus (Lesueur, 1840) from Northern and Southern Atlantic Drainages of Me´xico

A morphometric comparison was performed on specimens of blue catfish (Ictalurus furcatus) from northern (Lower Rı´o Bravo) and southern (Chiapas) Me´xico in order to identify diagnostic characters that allow their discrimination. The discriminant function analysis determined three characters to be highly diagnostic to separate the two groups of specimens: the southern group [SG] has a shorter anal base (mean 5 3.4 times in standard length [SL], range 5 3.1 to 3.7) vs northern group [NG] (mean 5 2.9 times in SL, range 5 2.7 to 3.1), a lesser head width (mean 5 6.0 times in SL, range 5.1 to 6.8) vs NG (mean 5 5.6 times, range 5 5.3 to 6.0), and a lower number of anal rays (mean 5 26, range 5 24 to 28) vs NG (mean 5 31, range 5 29 to 34). Additionally, 14 other characters were also different (P , 0.01) between both groups. All these characters support the taxonomic validation of Ictalurus meridionalis (Gu¨ nther 1864) for the individuals of SG that are currently included in I. furcatus Lesueur. Studies on comparative osteology and molecular genetics of both forms are needed for the clarification of their taxonomic status

Age Appropriate Wisdom? Ethnobiological Knowledge Ontogeny in Pastoralist Mexican Choyeros

We investigate whether age profiles of ethnobiological knowledge development are consistent with predictions derived from life history theory about the timing of productivity and reproduction. Life history models predict complementary knowledge profiles developing across the lifespan for women and men as they experience changes in embodied capital and the needs of dependent offspring. We evaluate these predictions using an ethnobiological knowledge assessment tool developed for an off-grid pastoralist population, known as Choyeros, from Baja California Sur, Mexico. Our results indicate that while individuals acquire knowledge of most dangerous items and edible resources by early adulthood, knowledge of plants and animals relevant to the age and sex divided labor domains and ecologies (e.g., women’s house gardens, men’s herding activities in the wilderness) continues to develop into middle adulthood but to different degrees and at different rates for men and women. As the demands of offspring accumulate for parents with age, reproductive aged adults continue to develop their knowledge to meet their children’s needs. After controlling for vision, post-reproductive adults’ show the greatest ethnobiological knowledge. These findings extend our understanding of the evolved human life history by illustrating how changes in embodied capital and the needs of dependent offspring predict the development of men’s and women’s ethnobiological knowledge across the lifespan

Composición y abundancia de búhos en el Parque Nacional Sierra de San Pedro Mártir, Baja California, México

La composición y abundancia de búhos fueron determinadas estacionalmente en cuatro sitios del Parque Nacional Sierra de San Pedro Mártir, Baja California (PNSSPM), México, mediante la técnica de reclamo-escucha de octubre 2017 a agosto 2018. Un total de 60 registros de siete especies fueron obtenidos (Tecolote Oyamelero Norteño Aegolius acadicus, Búho de Cara Canela Asio otus, Búho Cornudo Bubo virginianus, Tecolote Californiano Glaucidium californicum, Tecolote del Oeste Megascops kennicottii, Tecolote Ojos Oscuros Psiloscops flammeolus, y Búho Moteado Strix occidentalis). La especie con mayor frecuencia promedio de registros (individuos/h) fue B. virginianus (4.04), mientras que las otras especies registraron frecuencias de 0.2 (S. occidentalis) a 1.1 (M. kennicottii y A. otus). Dos especies fueron residentes permanentes (B. virginianus y M. kennicottii), una visitante veraniega (A. acadicus), una visitante invernal (A. otus), y tres visitantes ocasionales (P. flammeolus, G. californicum y S. occidentalis). La riqueza de especies de búhos en el PNSSPM incrementó en invierno debido a la presencia de especies migratorias.The composition and abundance of owls were seasonally determined at four sites of the Sierra de San Pedro Mártir National Park, Baja California (PNSSPM), Mexico, by means of the call-listening technique from October 2017 to August 2018. A total of 60 records of seven species was obtained (Northern Saw-whet Owl Aegolius acadicus, Long-eared Owl Asio otus, Great Horned Owl Bubo virginianus, Northern Pygmy-Owl Glaucidium californicum, Western Screech-Owl Megascops kennicottii, Flammulated Owl Psiloscops flammeolus, and Spotted Owl Strix occidentalis). The species with the highest average frequency of records (individuals/h) was B. virginianus (4.04), while other species recorded frequencies from 0.2 (S. occidentalis) to 1.1 (M. kennicottii and A. otus). Two species were permanent residents (B. virginianus and M. kennicottii), one summer visitor (A. acadicus), one winter visitor (A. otus), and three occasional visitors (P. flammeolus, G. californicum and S. occidentalis). The species richness of owls in the PNSSPM increased in winter due to the presence of migratory species

Composición taxonómica y abundancia espacio-temporal de la ictiofauna del Río Presidio, Sinaloa, México

Abstract: Taxonomic composition and spatio-temporal abundance of the ichthyofauna in Presidio River, Sinaloa, Mexico. The Rio Presidio in the southern Sinaloa, Mexico belongs to Nearctic-Neotropical zoogeographical transition zone, where its fish fauna could manifest changes in the abundance and distribution of the species during rainy and dry periods. The main objective of this study was to describe the taxonomic composition and spatial and temporal abundance of the fish fauna from the lower and middle Rio Presidio, by means of bimonthly samplings from April 2008 to February 2009. Forty fish species (39 native and 1 exotic) belonging to 32 genera and 19 families were registered. Two families (Gerreidae and Poeciliidae) contained the highest numbers of species (five and four, respectively). Six species (Lile stolifera, Oreochromis aureus, Awaous banana, Anchoa analis, Gobiomorus maculatus and Atherinella crystallina) in this order of importance contributed with almost 49 % of the total fish abundance. Species richness and salinity showed a direct relationship and an inverse relationship with the altitude. Based on the coefficient of similarity of species among sites two fish assemblages were identified. The first assemblage formed by species from marine derivation (peripheral) occurring in the lower part of the river, and the second assemblage by secondary freshwater species in the middle part. The higher fish species similarity observed in August and September was under the influence of the highest flows of the rainy period. Twenty-seven 27 species showed affinity to the Tropical Eastern Pacific Region, six species to the Neotropical region and two to the Nearctic region (Dorosoma smithi and Ictalurus cf. pricei ); one species has an Amphiatlantic distribution (Mugil curema), another is circumtropical (Mugil cephalus), two species have Amphiamerican distribution (A. monticola and G. cinereus), and one is exotic (O. aureus). Rev. Biol. Trop. 66(2): 848-862. Epub 2018 June 01. Key words: fish fauna; distribution; abundance; zoogeography; ecogeography

Seasonal pattern of the fish assemblage of El Conchalito mangrove swamp, La Paz Bay, Baja California Sur, Mexico

The seasonal changes in fish assemblage structure and the importance of El Conchalito mangrove swamp was assessed from October 1996 to August 1997. A modified stationary flume net was deployed at the swamp channel just before high tide and operated continuosly until the neap tide during the full moon. A total of 35,138 fish specimens were caught, belonging to 34 species included in 26 genera and 16 families. The fish assemblage changed with seasons, the fish assemblage had the highest species richness (21) and highest relative dominance index (0.77) in summer, but the highest Shannon diversity (2.7 bits/ind.) and Pielou evenness (0.73) in winter. Fish assemblages of summer and autumn had the highest similarity (68%), which reflects environmental changes that drives a sequential pattern in community structure between summer-autumn and autumn-winter clusters. Dominant species also showed a seasonal alternation between Eucinostomus currani (autumn), Albula nemoptera (winter) and Anchoa ischana (spring and summer) by numbers, whereas Diapterus peruvianus (autumn), Mugil curema (winter), Sphoeroides annulatus (spring) and A. ischana (summer) were the dominant species by biomass. The structural analysis of the fish community revealed four dominant species, seven common species and 23 rare species. The importance of the mangrove area of El Conchalito estuary is demonstrated based on the diversity of marine fishes that use this ecosystem as primary habitat for nursery, foraging and recruitment areas, and by its low disturbed conditions

Freshwater fishes and water status in Mexico: A country-wide appraisal.

Mexico is the southernmost country in North America, and extends into Central America, south of the Isthmus of Tehuantepec. The northern half of M´exico is located on the Temperate belt and is arid in character (Nearctic), while the rest is within the Tropical belt (Neotropical). Climate varies from extremely temperate desert in the north, to tropical humid in the south.M´exico has more than 500 freshwater fish species, about 271 of them country endemics, and approximately 48 endemics from binational basins. There are still some 30–40 fish species not yet described. There are 563 fish species colonizing coastal flood plain species. In addition to the numbers of colonizing fishes, the burden of introduced exotics has also been growing. In 1904, only 4 species were recognized as exotics; by 1997 the number had increased to 94, and by 2008 to 11